1. Field of the Invention
Embodiments pertain to in-vehicle radio frequency signal reception, and more particularly to providing signal tuning information for signal reception areas in which the vehicle is located.
2. Related Art
Many motor vehicles (e.g., automobiles, trucks) are equipped with radio receivers that receive radio signals from commercial radio broadcast stations (e.g., AM, FM). These radio receivers are typically equipped with means (e.g., conventional pushbuttons located on the receiver's front panel) that allow a radio listener to select one of several preselected radio frequencies for tuning and listening to content carried by the signal. At a particular geographic position, therefore, the listener may choose among several preselected commercial radio broadcast stations whose radio signal reception areas encompass the receiver's position. FIG. 1 illustrates motor vehicle 10 operating within reception area 12 of a signal broadcast by commercial broadcast transmitter 14. When in reception area 12, an occupant of vehicle 10 presses a pushbutton to select the signal frequency of transmitter 14.
Since the number of available preselected tuning frequencies is typically limited, when a motor vehicle is moved outside the signal reception areas of the broadcast stations whose frequencies have been preselected by the listener, the listener must then manually select broadcast signal frequencies for new signal reception areas. As illustrated in FIG. 1, for example, as vehicle 10 travels (depicted by the arrow) beyond reception area 12, the listener must find (e.g., manually tune or use a frequency scanning feature) frequencies in coverage areas 16 and 18 in order to receive signals from transmitters 20 and 22, respectively.
It is often difficult for a listener operating a vehicle outside of a home listening area (e.g., area 12) to discover one or more commercial radio stations that broadcast subject matter in which the listener is interested. While many in-vehicle radio receivers have a frequency scan feature, this feature often does not lock on to low power broadcast station signals, or to signals in acceptable but weak signal reception areas. Or, the scan feature locks on to a station during broadcast of an advertisement or other non-content related subject, so that 1.5 the listener is unable to determine the commercial broadcast content format (e.g., rock and roll music, classical music, news) of the locked-on signal. A listener traveling in vehicle 10 who normally listens to classical music in home reception area 12 must then tune to many different frequencies in reception areas 16,18 in order to continue listening to, for example, classical music. Similarly, a listener who travels to reception area 18 and who wants to receive local information (e.g., motor vehicle traffic information for highways within area 18) will have a difficult time determining which broadcast stations within area 18 transmit such local information. It is therefore desirable to provide a way for a motor vehicle radio listener to determine what radio frequencies are available at a particular geographic location, and furthermore to identify stations that broadcast in certain subject format categories at the location.